Spark plug



April 25, 1933 A. E. ANDERSON 1,905,957

SPARK PLUG Filed Nov. 8. 1932 24 INVENTOR.'

zygus E Hide/san Patented Apr.' 25, 1933 ATsNr AUGUBT E. ANDERSON', 0F MGNTGLAIB, NEW JERSEY SPARK PLUG' Application med November 8, 1932. Serial No. 841,765.

My invention relates to spark plugs for internal combustion engines, and more particularly designed as an improvement upon the devices described and claimed in my co pending application filed April 11, 1932, Se-

rial No. 604,592. Y

One object of my invention is to place an insulated wall directly between the elec-V trodes in the spark gap 1n order to concentrate the hi h voltage current to one spot or to one surgace of the electrodes. It is a well known fact that the high voltage current generally used in the combustion engines of today will find other paths than 5 through the gap of the, electrodes, thereby weakening and sometimes fouling the spark plug. With theinsulated wall, however, as shown in the accompanying drawing, these drawbacks are not only eliminated but la hotter spark i's obtained and with more eiiiciency at all times.

My other object providing an insulated wall between the electrodes, is to form a fiat spark rather than around spark as would be the case if the insulated wall were not there. It has proved to be lof great advantage to lire the compressed fuel charge with a ilat spark because the gases are more completely burned and therefore give a quicker action and more power to the engine.

Still another object of providing an insulated wall between the gap of the electrodes, is that by this wall the grounded electrode is completely insulated from the high voltage current or central electrode ex Acept across the edge of an insulated wall to the grounded electrode, and thereby eliminating the chances of fouling the spark plug by carbon or oil. If it hap cned that carbon or oil should deposit on t e said wall, the action of the electrical current and the heat would burn away all such deposits, and would not foul the spark plug but rather act as a stepping stone to the grounded electrode. Still another object with the said insulating wall 1s tobe able to obtain the advantage of a longer spark gap. As the edectrodes burn away, I have found that with the support of this wall, the spark would jump a greater distancethan if the said insulated wall were removed. Furthermore, with this 1 advantage the spark gap would not have to be adjusted to a set gap, as is now the case with the average spark plug.

ln the accom anying drawing, `one embodiment of my invention is illustrated, and Fig. 1 shows a longitudinal, axial section of the improved spark plug;

Fig. 2 a transverse section along line 2-2 @e of Fig. l and v Fig. 3 a fragmentary sectional view of the lower portion of the spark with a slight modification of my improved device.

In the drawing reference numeral 10 repre- @s sents the metal housing of the plug with a securing nut 11 threaded thereon as at 3l to hold the dielectric or porcelain insulator 12 in position therein. The insulator is in the usual manner provided with an enlarged body m portion 9 tapering into the upper neck portion 21 by way of a shoulder 20 and likewise tapering downwardly into the shank24 by way of a shoulder 23. Corresponding seats with packings forl said shoulders are 75 rovided in the nut 11 and housing 10 all in own manner. v

The neck portion 21 of the insulator extends throu h a corresponding opening of the nut 11 w 'ch latter is preferably rounded ao or dome-shapedto prevent tampering with the plug after its assembly. Into the top of the neck portion' the electrode 15 is threaded, extending with its long narrow portion. right through the enlarged bore of the in a5 sulator 12 to its lower end. Above the head 16 of this electrode 15 the same is ada ted'to receive a screw cap 17 for securing the cad-in wire. y

A11 annular space 14 is provided in the eX- atVV teriorly threaded end 19 ofthe housing 10 around the insulator shank 24. The latter has in its lower end a fairly deep chamber 13, opening downwardly and within this chaml ber is urnished, as an extension to the pore5 celain insulator, a tapering annular wall or curtain 26, the lower edge of which terminate about level with the lowermost end of the electrode 15, but well within the lower edge or the chamber. o.

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straight 26 and the end of the electrode 15. Fromthere it runs straight up ashort distance In the end portion 19 of the housing is secured the ground electrode v18, preferably in the form of a straight, short pin-'which extends across the annular space 14 and through `an enlarged opening 27 in the shank 24 and terminating in the chamber 13 near the edge of the curtain or tapering wall 26 and about level therewith.

As in my above-named copending application, the spark gap. 25 is also here located within the chamber 13 formed in the end of- 4straightxarm 29 in the lower end 13 of the housing, but instead ofruuining through an opening in the porcelain shank 24 as in Fig. 1, it is now bent around the lower edge of the shank with an arm running upward in about inclination into the chamber 13 uptoa point about level with the edge of the curtain above said edge and forming a ti 30.

By this means assemblin of t e parts isfacilitated while retaining t e advantages of the flat spark and the long gap.

It should be. understood that the invention is not to the details of construction here shownand disclosed but that those may be variedV widely without departing from the spirit of the invention as defined bythe aims.

I Claim: A j 1. In a spark plug having the usual electrodes, a metal housing member and an insu- A lator core member firmly seated therein, said core member being providedjwith a downwardly open chamber, an annular space being formed between the lower ends of said members; the main electrode bein mounted axially in said core members and t e ground electrode secured in said housing memberand extending across said space into said chamber, the'spark points being situated within said chamber well be ond the loweredge of the core member;t e combination with Ameans forming an obstruction in the s :rk gapetlie'reby creating a substantially ark tween the spark points.

aV spark plug havin the usual electrodes, 'a metal housing mem r and an insulator core member firmly seated therein, said core member bein provided with 'a downwardly open cham r`,`an annular space being formed between the llower ends of said members); the combination with an annular wall forming a continuation of the core .member within said chamber and terminatin well within the chamber, the main `electr e being mounted axially in the core member with its -spark point substantially level with the .edge of .said annular wall, the "ground electrode being secured in said housing member and having its spark-point situated in said chamber outside of said :annular wall, the edge of said wall thus forming an obstruction between the spark points in the spark gap.

' 3. In a spark plug-having the usual electrodes, a metal housing member and an insulator core member firmly seated therein, said core memberzbeing provided with a downwardly open chamber, an annular space being formed between the lower ends of said wall forming a continuation oi the core member withinsaid chamber and terminating well within the chamber,' the main electrode being mounted axially in the core member with its spark point substantially level with the edgeof said annular wall,- the ground electrode being secured in saidliousing member, and havin an upwardly inclined arm terminating with a spark point extending intosaid chamber above the edge of the annular wall, said edge vthus forming an obstruction between the spark points in the spark gap.

members; the. combination with an annular "4.' Ina Spark plug havin the usual elecl trodes, a metalhousing mem er and an insulator core member firmly seated therein, said4 core member beingeprovided with a down r, an annular space bewardly open cham ing vformed between the lower ends of sai-d members; the main electrode bein mounted axially -in said core members and t e ound electrode secured in said housing mem er and extending .across said space into said chainber, the As'pirk points being situated within said cham r well beyond the lower edge of the core member; the combination with means forming an obstruction in the spark ap, thereby creating a spark gap of more t an ordinary length. 5. In a spark'plug having the usual electrodesnga metal housing member. andanv insulator core member seated therein, said-cere member being provided with an open ended chamber, an annular space being formed between the said members; the main electrode being mounted in said core member and the ground electrode secured in said housing member and extendm across said space into said chamber, the spar points being'situated within said chamber; the combination with means forming an obstruction in the spark gap, thereby creating a substantially fiat spark between thespark points.

`In testimon whereof I aiix my signature. U GUST `E. ANDERSON. 

